Why are people so arsed about them either way? Crypto seems to get so many people wound up. I get bitcoin chewing up all the energy supply in Kazakhstan etc but most nfts are on cardano or this new shit and use hardly any energy. As a useful form of tech it's about the only thing out there with any chance of wrestling some money back from big tech directly to artists.
Not really true about the cardano bit. There are many, many other blockchains out there e.g. Cosmos, Ethereum, Terra, Solana, etc. and most of them have NFTs on them too. NFTs are simply digital assets on a blockchain, which is also erm...digital.
There are mainly two mechanisms for processing and validating transactions and blocks on a blockchain i.e. proof of work (PoW) and proof of stake (PoS). Bitcoin and ETH are a few of the coins that run on PoW, which loses out to PoS type of coins, when it comes to energy efficiency.
Basically there's 3 main things to look at when you want to build on a blockchain - scalability, security and speed.
PoS (non-BTC) = faster speed, lower energy consumption
PoW (BTC, ETH) = better security and decentralisation, higher energy consumption, slower speed
CoinBureau (yes, youtuber) does a fantastic job in explaining everything you need to know bout crypto. And he does it more properly and professionally unlike most of the nutters out there.